More than 15 months after landing in Jezero Crater on Mars, NASA s Perseverance rover has finally begun its hunt for ancient life in earnest.
On 28 May, Perseverance ground a 5-centimetre-wide circular patch into a rock at the base of what was once a river delta in the crater. This delta formed billions of years ago, when a long-vanished river deposited layers of sediment into Jezero, and it is the main reason that NASA sent the rover there. On Earth, river sediment is usually teeming with life.
Images of the freshly ground spot show small sediment grains, which scientists are hoping will contain chemical or other traces of life. Poet William Blake s To see a world in a grain of sand comes to mind, wrote Sanjeev Gupta, a planetary geologist at Imperial College London, on Twitter.
Nick Bostrom has a paper on whether among other things we should hope to find evidence of life, or not, on other planets. Honestly, I forget what it says, but I think he thinks if we find evidence of life, that’s a very bad thing, as it suggests somehow the Great Filter is ahead rather than behind us. But it might be the opposite. I can’t recall. But I think it would be pretty cool to find little fossilized germs, our possible doom notwithstanding.
